If you want to send a message without any chance of it being intercepted then end-to-end encryption services are the way to do it. Governments and intelligence agencies can’t even intercept these messages, without compromising the phone they’re sent or received on, because the tech companies themselves don’t even have access.

In the pursuit of protecting people’s privacy, in the wrong hands these messaging apps can be dangerous. Aleks discovers how the Taliban used WhatsApp to help them sweep through Afghanistan and take Kabul, without a bullet being fired.

Unless you turn off the internet it's impossible with technology like WhatsApp, Telegram and Signal to let the ‘good’ guys use it while restricting the ‘bad’ guys. Aleks hears why turning off the internet is not the answer because it often favours those who are trying to oppress rather than the people who need help.

Aleks learns that while the Taliban were using WhatsApp to organise and disarm those who may have tried to resist their takeover of Afghanistan, many Afghans who were desperately trying to escape Kabul relied on WhatsApp to connect and keep in touch with military officers and diplomats in order to get to and through the right gate and onto flights to safety. For some, when their phone battery ran out so did their hopes of escape.

"WhatsApp has provided a lifeline to millions of people around the world and we're grateful to have played a small role in helping people in Afghanistan. Of course, WhatsApp requires a mobile connection, and anyone who has spent time in Afghanistan knows its complex terrain often times requires multiple forms of communications to reach across the country." WhatsApp spokesperson.

Producer: Kate Bissell